A traveler assembly is employed on a sailboat to provide a movable anchoring point for a block, cleat or other marine hardware item. For example, a traveler assembly is often mounted transversely near the stern of the boat to anchor a block controlling the main sheet. Such a traveler assembly may also be used to control the leech and foot tension of a genoa when the genoa is set and drawing under load.
The usual traveler assembly includes a track or slide that is secured to the boat structure and a car that rides on the track. The block or other marine fixture is secured to the top of the car. On smaller sailboats, the car component of the assembly may simply be a key or slider which slides in a keyway or slide defining the track. However, on larger boats, particularly cruisers and racing craft whose traveler assemblies are subjected to very high vertical and lateral loads, a larger, much more rugged, mechanically complex assembly is utilized.
In the latter type of traveler assembly of interest here, the track is in the form of an extruded member having a cross-sectional shape which makes it quite rigid and which defines flat rails on which the car can ride. The cross sections of some tracks are X-shaped and some are I-shaped. The traveler car is fitted with wheels having flat peripheries and which roll along the rails defined by the track. For example, in the traveler assembly incorporating an I-shaped track, the car straddles the track and its wheels engage the upper and lower arms of the I at opposite sides of the track. The car associated with the X-shaped traveler track also straddles the track and is fitted with wheels which engage under rails defined by the upper arms of the track.
There also exists an assembly with a modified X-shaped track whose lower arms splay out sideways beyond the upper arms, thereby defining a pair of lower rails which are also engaged by the car wheels. When the car is subjected to compression loads, the car wheels roll along the lower rails and, when the car is placed under tension, the wheels roll along the upper rails defined by the track.
In many traveler assemblies, the tracks are bent horizontally or vertically to some extent either intentionally to conform to the structures to which they are anchored or due to distortion caused by the heavy loads applied to them. Therefore, the cars must fit relatively loosely on such tracks to ensure that they can travel from end to end despite such bends. Some prior assemblies are disadvantaged because, when they are subjected to relatively high side loads, their cars, being loosely fitted to the track as aforesaid, cock to such an extent that they scrape or chafe against their tracks as they move along the tracks. This causes noise and excessive parts wear. Also, of course, such scraping inhibits the motion of the car along the tracks.
Furthermore, the rail and the wheel surfaces in the prior assemblies usually achieve point contact. Consequently, when a car cocks due to a side load, the peripheries of its wheels are no longer flush with the rail surfaces and the entire side load is transmitted to the rails at the edges of the wheels. Therefore, after only a relatively short time, the wheel edges tend to wear grooves in the rails or become worn themselves thereby loosening the fit between the car and the track. That, in turn, promotes even more chafing, parts wear and interferes generally with the proper operation of the traveler assembly.
The traveler assembly described above employing the modified X-track is able to handle side loads applied at angles of up to 180.degree.. However, in order to do this, it has an unusually wide cross section so that it takes up a relatively large amount of space on the boat and requires a proportionately wider bridge if it is mounted on such a bridge extending over a companionway, for example. Furthermore, the track in that particular prior assembly cannot be bent either in the vertical or the horizontal direction. Therefore, it has to be mounted on a perfectly straight flat surface if it is to operate properly.